This invention relates to body voltage and body temperature measurement instruments.
It has been found in laboratory tests that ovulation in mammals, including humans, is accompanied by a small but measurable rise in body temperature and a small but measurable rise in the voltage between spaced apart points on the exterior of the body, e.g. between the thumbs. In recent years, efforts have been made to utilize these two effects to detect ovulation in humans for use in the rhythm method of birth control. The rhythm method of birth control requires that couples abstain from intercourse for a period before and after ovulation. It is believed that the ovum is susceptible to fertilization for about 24 hours after its release, and that the sperm deposited in the female reproductive tract is capable of fertilizing the ovum for about 72 hours. Thus if intercourse does not occur from three days before ovulation to one day after ovulation, the sperm cannot fertilize the ovum and conception will not take place.
The difficulty in practicing the rhythm method is that ovulation time differs in every woman, and although there are laboratory instruments for detecting the onset of ovulation, there are no presently available consumer instruments that can be used by the average woman. Various consumer instruments have been proposed, some utilizing temperature alone, some utilizing voltage alone, and some utilizing both. The instruments which work by voltage or temperature alone are unreliable because there are reasons why a woman's temperature, or voltage, will rise other than ovulation. The instruments which take both temperature and voltage into consideration will, it is believed, probably correctly identify ovulation by the correlation between a temperature rise and a voltage rise, which will eliminate those physiological events which cause a rise of temperature alone, or of voltage alone. The difficulty with the type of instrument which utilizes both indications is that the presently proposed consumer designs are relatively complex and costly and thus would be available only to the wealthy. The principal object of this invention is to provide an instrument for detecting ovulation in terms of both body temperature and voltage which is low enough in cost to be available to the average woman.
Another object of this invention is to provide an instrument of the above noted type which is small enough to be held in the hand.
A further object of this invention is to provide an instrument of the above noted type which is simple to read and to operate.
Other objects and advantages of the invention will be apparent from the detailed description of the invention herein.